简介:Anexperimentofadaptivepolarizationmodedispersion(PMD)compensationfor40-Gb/sreturn-to-zero(RZ)opticalcommunicationsystemisreported.Intheexperiment,degreeofpolarization(DOP)isusedasfeedbacksignalandparticleswarmoptimization(PSO)methodisadoptedaslogiccontrolalgorithm.Thecompensationtimeisabout200ms,thecompensateddifferentialgroupdelay(DGD)isupto30ps,andbiterrorrate(BER)of10^-9isreachedwhenPMDcompensationisemployed.
简介:主动红外入侵探测器是目前周界防范系统中的首选产品,亦是新修订国标GB10408系统标准中的主要项目。本文作者实际参与了GB10408.4-2000《主动红外入侵探测器》标准的制定,特针对该标准中部分重点提供个人心得与体会与读者分享。
简介:<正>Foranoddfunctionf(x)definedonlyonafiniteinterval,thispaperdealswiththeexistenceofperiodicsolutionsandthenumberofsimpleperiodicsolutionsofthedifferentialdelayequation(DDE)(?)(t)=-f(x(t-1)).Byuseofthemethodofqualitativeanalysiscombinedwiththeconstructingofspecialsolutionsaseriesofinterestingresultsareobtainedontheseproblems.
简介:Inthiswork,webrieflydiscussanovelclassofmodifiedgravitylikef(T,TG)gravity.Inthisbackground,weassumethenewagegraphicversionofpilgrimdarkenergyandreconstructf(T,TG)modelsfortwospecificvaluesofs.Wealsodiscusstheequationofstateparameter,squaredspeedofsoundandwDE-wDEplaneforthesereconstructedf(T,TG)models.Theequationofstateparameterprovidesphantom-likebehavioroftheuniverse.ThewDE-wDEplanealsocorrespondstoΛCDMlimit,thawingandfreezingregionsforbothmodels.
简介:Theoneplusone(1+1)modeofhydrosilationreactionofladderlikecis-isotaticpolyallylsilsesquioxane(AllyI-T)andpolyhydrosilsesquioxane(H-T)usingdicyclopentadienylplatinumdichloride(Cp2PtCl2)asthecatalystleadstotheformationofanewpolyorganosiloxane(POS).ThepresenceofnanoscaletubularstructureintheproductPOSwaspreliminarilyprovedbyIR,1H-NMR,differentialscanningcalorimetry(DSC),X-raydiffraction(XRD),gelpermeationchromatography(GPC),atomicforcemicroscopy(AFM)andmolecularsimulation.